#include <stdio.h>

int main(int argc, char *argv[]) 
{
	int x1,y1,x2,y2,move();
	scanf("%d,%d",&x1,&y1);
	scanf("%d,%d",&x2,&y2);
	if(move(x1,y1,x2,y2))printf("Yes.\n");
	else printf("No.\n");
}
int move(int x1,int y1,int x2,int y2)
{
	if(x1==x2&&y1==y2)return 1;
	else if(x1>x2||y1>y2) return 0;
	
	if(move(x1+y1,y1,x2,y2))return 1;
	if(move(x1,y1+x1,x2,y2))return 1;
	
	
}